Various approaches have been used in the past in attempts to increase the adhesion between fluoropolymers and substrates or filler materials.
U.S. Pat. No. 3,787,281, Effenberger, discloses a process for bonding polytetrafluoroethylene to glass, fibers or plates, using a hydrolyzable silane or a methacrylato chromic chloride as bonding agent.
Canadian Patent No. 764,537 Bowman, discloses adhesive compositions suitable for use with fluorocarbon polymers comprising reactive (hydrolyzable) silanes or siloxanes. The fluorocarbon polymer is optionally pretreated with a solution of sodium in ammonia or a solution of sodium naphthalene in tetrahydrofuran.
U.S. Pat. No. 3,804,802, Bergna, discloses composites of thermoplastic resins, including polyfluoroolefins, with glass fiber materials utilizing a nitrate-containing coupling agent to increase adhesion between the components.
U.S. Pat. Nos. 4,902,444 and 5,000,875 disclose melt processable fluorinated tetrafluoroethylene copolymer and terpolymer compositions that are treated with a fluorinating agent to remove unstable end groups, then compounded with electrically conductive agents or thermally conductive fillers.
U.S. Pat. No. 5,024,871, Arthur, discloses a ceramic-filled fluoropolymeric composite wherein the filler, preferably fused amorphous silica, is coated with a zirconate or titanate coating. Said composite possesses excellent thermal, mechanical and electrical properties. U.S. Pat. Nos. 5,061,548 and 5,384181, Arthur, disclose similar composites wherein the surface coating agent is a silane.